Equipment focus: Wirtgen W 210i cold milling machine

After the Wirtgen W 210i cold milling machine had rehabilitated the start/finish stretches of the TT Circuit, a motorcycle racing pro put the ‘new’ track to the test.

The Wirtgen W 210i cold milling machine profiled the start/finish stretches at a feed rate of 3-6 metres a minute.

Because the cabin can move out over the right and left zero-clearance sides of the machine and rotate through 110 degrees in all positions, the operator of the W 210i has an unobstructed view of the work area, even when traveling in reverse.

Using a 4m-long level, a worker for contractor BAM measures the evenness of the rehabilitated track surface.

After the Wirtgen W 210i cold milling machine had rehabilitated the start/finish stretches of the TT Circuit, a motorcycle racing pro put the ‘new’ track to the test.

The Wirtgen W 210i cold milling machine profiled the start/finish stretches at a feed rate of 3-6 metres a minute.

Because the cabin can move out over the right and left zero-clearance sides of the machine and rotate through 110 degrees in all positions, the operator of the W 210i has an unobstructed view of the work area, even when traveling in reverse.

Using a 4m-long level, a worker for contractor BAM measures the evenness of the rehabilitated track surface.

A Wirtgen W 210i cold milling machine with an FCS super-fine milling drum has been used to rehabilitate one of Europe’s leading motorcycle race tracks – the TT Circuit in Assen, Netherlands.

After years of racing on the 4.5km circuit – the only world championship track designed specifically for motorcycles – corrugations of between 3mm and 8mm high had formed along the start and finishing stretches. As a result, when drivers braked before turns, their bikes would begin to judder and become uncontrollable.

As this posed an excessive safety risk for drivers, GMS Fahrbahnsanierungen was appointed to profile the raceway over an area of 3,000 square metres to restore the surface’s skid resistance using a super-fine milling process, which removes surface deformations from the roadway to produce uniform, level surfaces.

"We elected to use a Wirtgen W 210i cold milling machine with an FCS LA 6x2 super-fine milling drum," GMS site manager Ernst Kugel says. "Unlike a standard milling drum, it is fitted with 672 cutting tools rather than the usual 168."

In contrast to standard milling drums, super-fine milling drums – also referred to as micro fine milling drums – have tool spacing of less than 6mm. This enables them to produce a very finely textured road surface with a maximum milling depth of 3cm.

With its Flexible Cutter System (FCS), Wirtgen operators are able to switch between milling drums with different tool spacings or working widths to cater to different applications. Drums can be changed quickly in just a few swift moves, the company says.

GMS general manager Torsten Meyer says this is a major advantage and a key factor for the efficient operation of large milling machines, adding: "It’s important for us to be able to use the machines flexibly and thus cost-efficiently."

GMS used the Multiplex levelling system on the TT Circuit rehabilitation project’s super-fine milling work because it precisely measures extended longitudinal irregularities by combining several sensors on one or both sides of the machine (such as cable, ultrasonic and cylinder sensors), Wirtgen says, adding that longitudinal irregularities can therefore be levelled out very effectively, achieving high-precision levelling results.

"The quality of the road surface is very good; we could not detect any residual unevenness," Kugel says.

The Wirtgen W 210i features an Operator Comfort System (OCS) which has a hydraulically moving and swivelling cabin. This can be quickly and efficiently be shifted into a position that gives the machine operator optimum visibility.

Other features of the cab are camera transmission, precision joystick control and a powerful automatic climate control system.